Barnaby Joyce won't repay more than $5,000 billed to taxpayers for attending State of Origin, NRL finals

Barnaby Joyce says his attendance at the State of Origin was for "official business".

AAP: Alan Porritt, file photo

Agriculture Minister Barnaby Joyce says he will not repay thousands of dollars of taxpayers' money he spent going to rugby league matches last year.

The ABC has calculated Mr Joyce claimed $5,312.57 for flights, travel allowance and government car costs to attend State of Origin II in Sydney on June 13, 2012, and NRL finals matches on September 14 and 30 later that year.

His expense claims say he was on official business, something Mr Joyce reiterated today.

"Because you're an official guest. You've been officially invited by the National Rugby League, the National Rugby League has every right to have access to politicians," he said.

Under the guidelines, official business "is limited to properly constituted meetings of a government advisory committee or task force, or functions representing a minister or presiding officer".

The Nationals MP says the NRL wanted to talk to him about several issues, including drugs in sport.

The claims included $741.20 for flights between Brisbane and Sydney for a family member on September 30 and October 1, 2012.

Mr Joyce says he would have to check, but he probably took his wife or one of his daughters.

He says the claims were within the rules, but he would not have a problem with the guidelines being changed.

"I've got no problems whatsoever if they say from this point forward you won't go to meetings you've been officially invited to because that means I can spend more time at home, which I'm really at ease with," he said.

Hockey says expense claims an 'individual judgement call'

Treasurer Joe Hockey was quizzed on the ABC's 7.30 program about whether Mr Joyce was right to make the claims.

"If it was part of my work commitment, if I'm only invited because I am the Treasurer or the shadow treasurer, and I'm only there for that purpose, then it's part of work," Mr Hockey said.

"But you know, the fact is if anyone is abuses the system they should be held to account, of course they should, no matter what."

Host Leigh Sales asked Mr Hockey: "If I invited you to my wedding, would you think that was a work function?"